(a) Field of the Invention
The present invention relates to a method for manufacturing a solar cell.
(b) Description of the Related Art
Solar cells convert sunlight into electrical energy. Solar cells are diodes including a PN bond, and are classified into different types according to the materials that are used in a light absorbing layer.
Solar cells using a silicon layer as a light absorbing layer are classified into a crystalline wafer type solar cell and a thin film type (crystalline and amorphous) solar cell.
In the case of crystalline wafer type solar cell, the bonding characteristic of the P layer and the N layer is excellent such that output current and fill factor are satisfactory. In manufacturing the crystalline wafer type solar cell, after the PN bonding, the dopant is diffused by using a laser in a preselected region of the surface of the semiconductor in order to increase the dopant concentration in the region. The laser-induced diffusing of the dopant makes the doping layer thin and prevents recombination of an electron and a hole.
However, the laser-induced diffusing of the dopant damages the surface of the semiconductor.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.